i remember seeing somewere... that DDR2 has higher latency but it doesnt afect it... something about pin count, and something, makes DDR2 proccess much faster then DDR even though it has higher latency.
i know thats very vague(i dont remember the specifics), but in general it was stating that DDR2 is faster even with low latency's, i do not know however, if thy were refering to any DDR2 speed, or only at a sertain point. it could be at any speed.